In these years, the shortages of water has become a ______ problem.
| A．global | B．historical | C．chemical | D．local |
---May I borrow your paper? ---__________.
| A．By all means | B．Never mind |
| C．You are welcome | D．Don’t mention it |
_______, her hands shook constantly and violently.
| A．Knowing her son killed in the mine | B．When she knew her son was killed in the mine |
| C．Known her son killed in the mine | D．She knew her son killed in the mine |
For a moment nothing happened. Thenall shouting together.
| A．voices had come | B．came voices |
| C．voices would come | D．did voices come |
I was at a loss what to do next when an excellent idea suddenly` _______ me.
| A．knocked at | B．occurred to | C．happened to | D．knocked down |
One of the reasons____ he explained to us was ______ he had dreamt of doing so.
| A．why; that | B．that; that | C．why; because | D．that; because |